Author Topic: The moon and other astronomy stuff  (Read 12336 times)

David Martin

  • Thats Dr Oi You thankyouverymuch
Re: The moon and other astronomy stuff
« Reply #125 on: October 02, 2018, 09:41:22 pm »
It has the benefit that it is easily removable to attach a more solid foundation. I shall order the motor and think about how best to add a DSLR to the mount. Maybe drill a home and use a single bolt directly in the dovetail plate, or find a better camera mount.

Taken a more detailed look at it after removing the tube clamps. I took the declination adjustment apart. It is solidly built but the key part that is shoddy is the internals. These have greased friction bearings (bushes with a plastic slip washer) inside the machined casting. Unfortunately the bushes for the bearings are at one end a cheap penny washer and at the other an aluminium billet that has been formed but not finished after pressing. These have a fair amount of slop. The housing itself is well done and finished appropriately. Someone with a lathe could make a very nice job of a smooth set of bearings internally. Hopefully this will be sufficient for what I want to do. It does have a very sticky grease on it - I presume a shipping grease rather than one which should be used.

So if it does not work out as it is, a bit of metal work if I can find someone keen to fettle me some new bushes, possibly even find real bearings of the right size to use.

I can see why David A was so sniffy about it, but there is the capacity to build something that works well. It is very irritating when what could be a good piece of kit is spoiled by a bit of slapdash assembly. The slop at each bearing is about 0.25-0.5mm, sufficient that if it was a headset on a bike you would be wanting to get it looked at.
"By creating we think. By living we learn" - Patrick Geddes

David Martin

  • Thats Dr Oi You thankyouverymuch
Re: The moon and other astronomy stuff
« Reply #126 on: October 11, 2018, 11:21:02 pm »
I have managed to fit the camera mount to the baseplate. The motor has arrived and appears to work. All I need now are some clear skies and time.

"By creating we think. By living we learn" - Patrick Geddes

David Martin

  • Thats Dr Oi You thankyouverymuch
Re: The moon and other astronomy stuff
« Reply #127 on: October 14, 2018, 11:43:48 pm »
Clear skies (ish) and a small timeslot meant I could play.

Could have spent more time trying to get a perfect equatorial alignment, but got close enough for starters.

DSC_7724 by David Martin, on Flickr
DSC_7734 by David Martin, on Flickr
A few wisps of cloud appearing, and I've colour corrected to remove as much of the orange glow as I can. Generally happy that it will give me good RA stability. I did try the 150-600 lens but that is notoriously wobbly. Good for checking if the alignment is right though.



"By creating we think. By living we learn" - Patrick Geddes

fuzzy (retd.) AAGE

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Re: The moon and other astronomy stuff
« Reply #128 on: October 15, 2018, 11:08:28 am »
Not bad- nice and stable.
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